Найти: cos a и tg а, если sin a = 1/6

sin(a)^2 + cos(a)^2 = 1 => 1/36 + cos(a)^2 = 36/36 => cos(a)^2 = 35/36 => cos(a) = Корен(35) / 6

tg(а) = sin(a) / cos(a) => tg(a) = 1 / Корен(35)

Cos a=sqrt(1-sin^2a)=sqrt(1-1/36)=sqrt35/6

Tg a=sin a/cos a
Tg a=1/sqrt(35)=sqrt35/35